textproduct: Quad Cities

KEY MESSAGES

- Pattern change late week will result in increasing temperatures and humidity lasting at least through the weekend. This will result in a more summer-like feel due to the noticeably humid conditions.

- Due to increasing heat and humidity, near-daily chances for storms will be seen from Thursday PM into early next week. Some stronger storms and heavy rain will be possible.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 230 PM CDT Wed Jun 3 2026

Through Tonight: An area of high pressure centered over the Great Lakes and Ohio Valley region will continue to influence our weather locally. After highs in the low/mid 80s late this afternoon, temps will drop off nicely into the upper 50s to lower 60s tonight due to a dry air mass in place (dewpoints in the ~40s to around 50 F).

Thursday: Low and mid-level warm air and moisture advection will ramp up through the day due to increasing southerly flow near the surface and southwesterly aloft. This will lead to a significant increase in dewpoints with values reaching the lower 50s to lower 60s (east to west) across the outlook area. The persistent isentropic lift and development of diurnal instability (HREF SBCAPE between 500-1000 J/kg) may support isolated showers and storms during the afternoon/evening, favored across the west/northwest counties. The coverage of showers and storms looks to increase into Thursday night (40-80%, highest north and west of the Quad Cities) as more organized activity emanates out of northeast Kansas and northwest Missouri. Weak shear, with 0-6 km bulk values under 30 kts, will limit the overall strength of the storms. However, gusty winds would still be possible with the strongest cells. Locally heavy rainfall (1-2"+) is possible where repeated rounds of storms track through and this is most favored across the northwest counties.

LONG TERM /FRIDAY THROUGH WEDNESDAY/

Issued at 230 PM CDT Wed Jun 3 2026

Friday and through the weekend will feature a more active, yet messy upper level pattern. Going into Friday, the aforementioned ridge will have flattened out over the Central CONUS, resulting in a brief bout of zonal flow. Within this flow pattern, subtle bouts of vorticity will pass through the region. Near the surface, a weak baroclinic zone will set up, which will provide the necessary forcing for storms to develop Friday into Saturday. Plenty of moisture will be present at this point, owing to strong warm advection from a wide open Gulf. PWATs are forecast to increase well above seasonal norms, near ~1.75", which is around the 90-99th percentile (nearing daily max for some). Thus, any storm that develops will have the ability to drop efficient and heavy rainfall, even if brief. This rainfall is much needed, given such dry conditions as of late. A couple rounds of storms will be possible through the day Friday, with residual showers/storms in the AM and further development possible in the afternoon/evening or into Friday night.

Friday night into Saturday, we will see a more notable wave pass through the area from the northwest. This will help push out the weak boundary stalled out over the area Friday. With this passing through, better forcing and shear will move in through the night, which may support the potential for some stronger storms again. At this time, this looks like an overnight MCS may result. There remains some uncertainty amongst guidance, but all generally indicate a complex of showers and storms moving through the area. Model soundings show shear/instability profiles that would favor such. Although, we will see weaker instability overnight, leading to some uncertainty in any severe potential. Either way, this would bring another wave of much needed rainfall. SPC has a Marginal Risk (level 1 of 5) for severe storms for much of the outlook area for Friday/Friday night, and a Slight Risk (level 2 of 5) across the far northwest. The primary threat is damaging winds.

By midday Saturday, we will see upper ridging work into the area with a surface high pressure settling over the Great Lakes Region again. This should help kick out any remaining precipitation by the early/mid afternoon hours. From there, dry weather would be favored for the remainder of the day. Much uncertainty remains on the upper level pattern after Saturday. Global guidance wants to strengthen this ridge overhead and essentially create another blocking pattern. Although, this will be a messy block, as there will be an upper low slowly moving in from the southwest Sunday that can bring more chances for precipitation. Guidance does not quite agree on how far into the region this feature makes it, which will have some implications on precipitation chances. At this time, will stick with the NBM guidance, which introduces 20-40% PoPs into our southwest half of the area on Sunday, inching farther north each day following. The threat for severe weather is uncertain during this timeframe. Through this timeframe, guidance continues to favor above normal temperatures (mid-upper 80s) and humidity remaining higher.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 640 PM CDT Wed Jun 3 2026

Generally a VFR TAF cycle with the local area in between ridging to the east and a frontal system acrs the plains. South to southeasterly sfc winds will maintain 6-10 KTs overnight, then a little veer to the south to southwest mid to late Thu morning with them becoming gusty up to at least 20 KTs. High clouds will thicken as Thursday progresses, and some mid level AC may get into the CID VCNTY late in the period while convection percolates just off to the northwest.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.